Calipers and dividers



Patented May 27, 1890.

(No Model.)

W. H. STUART.

GALIPERS 0R DIVIDERS.

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UNITED STATES PATENT OFFICE.

\VILLARD H. STUART, OF CHIOOPEE FALLS, MASSACHUSETTS.

CALIPERS AN'D DIVIDERS.

SPECIFICATION forming part of Letters Patent No. 429,069, dated May 27,1890. Application filed June 29, 1889. Serial No. 316,065. (No model.)

. lowing to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it appertains to.

make and use the same, reference being had to the accompanying drawings,and to letters of reference marked thereon, which form a part of thisspecification.

Figure 1 of the drawings is a representation of this invention and isa'vertical section. Fig. 2 is an enlarged view of the same, the low endsbeing broken off. Fig. 3 is a side View, a section being taken throughthe operating-screw and nut-pawl. Figs. 4, 5, and 6 are details.

This invention relates to calipers and dividers; and it consists in thenovel construction and combination of parts, as hereinafter set forth.

In the accompanying drawings, the letters A A designate the legs of thecalipers, having at their ends the inner angular bearingsurfaces, as atz ,2, which are provided with a ball-and-socket joint.

A compressing bow-spring B, the ends of which engage notches in theouter portions of the upper ends of the legs opposite to the upperportion of the ball-and-socket joint, serves to hold the legs togetherand to give the outward action.

0 is a transverse threaded operating-screw, which passes through a slotd of the leg A to engage by its spherical end e a recessed hearing 11 ofthe opposite leg A.

F is an L-shaped pivoted half-nut, pivoted by its angular portion in theslot d on the outer edge of the leg A to engage the threads of theoperating-screw O. The pivoted halfnut F consists of a vertical stem orfingerpiece 7c and a horizontal concave threaded shoe Z. The stem 7c ofthe half-nut forms an acute angle with the outer edge of leg A. In

the angle thus formed is secured to the upper end of the stem 70 aspring m, which causes the threaded shoe Z of the half-nut to remain incontact with the operating-screw C. The under portion of the shoeZ isconcave and threaded, as above described, to correspond with the threadsof the screw 0 for the coarse and quick adjustment of the instrument.The are of each thread of the shoe is less than half the full thread ofthe screw, as shown. The operating-screw O is provided on its outer endwith a milled head a, whereby the screw can be easily turned in making afiner adjustment, if necessary, after the legs have been spread. Theinner end of the screw 0 is provided with a spherical or other suitablehead 8, formed at the extremity of a tapering portion 7". This head hasits bearing in the recess i of the leg A, and is retained therein by aU-shaped keeper 8.

The angular inner portions of the heads of the legs A A are usually madewith hemispherical recesses b on their opposing faces, to form bearingsfor the ball 0, when the legs are connected and held together by thebowspring B, so that a simple and effective joint is provided.

When the calipers are at rest, the half-nut F is held by its spring inconstant contact with the thread of the operating-screw, but is releasedby pressing against the stem or lever-arm 7a of said half-nut, thisoperation causing the latter to rise from the screw and permitting thelegs of the instrument to diverge under the retractive action of thebowspring.

Having described this invention, what I claim, and desire to secure byLetters Patent, 1s

1. The calipers and dividers comprising the connected legs, the screwhaving a ball-andsocket joint in one leg and passing through a slot inthe other leg, and the spring-pressed half-nut pivoted upon the latter"leg and engaging said screw, substantially as set forth.

2. The calipers and dividers consisting of the legs having aball-and-socket-joiut connection at their upper ends, and a bow-sprin gengaging notchesin said ends and tending to arm of said half-nut,substantially as set give said legs their outward movement, in forth. IOaddition to holding them together, the screw In testimony whereof Iaffix my signature in having a ball-and-soeket; jointin one leg andpresence of two Witnesses.

5 passing through a slot in the other 1eg,the \VILLARD II. STUART.

L-shaped half-n n1; pivoted upon the latter leg \Vitnesses: andengaging; said screw, and the spring in- JAMES ll. LOOMIS,

terposed between one of said legs and the FRED N. \VITHREL.

